Oracle
Metric recursive calls

Oracle Tips by Burleson Consulting

The
recursive calls Oracle metric maintains tables used for
internal processing. When Oracle needs to make a change to these
tables, it internally generates a SQL statement. These internal SQL
statements generate recursive calls.

Oracle MOSC documents also offer information regarding
"OPTIMIZING ORACLE7.1 DATABASE PERFORMANCE" including some great
points on the recursive calls metric:

"Recursive
Calls : occur because of cache misses and dynamic storage
extension. If the dictionary data is found in cache, a recursive
call is not
made and the data is read from cache directly. In general if
recursive calls
is greater than 4 per process, the data dictionary cache (described
below)
should be optimized and segments should be rebuilt with storage
clauses
to have a few large extents. Segments include tables, indexes,
rollback
segment, and temporary segments.

Also, Recursive calls should be fewer than user calls (less than
one-
tenth). Where there is an imbalance the aim should be to reduce
parsing.
review : recursive calls to user calls parse count to user calls.
High levels
of recursive sql may also be attributable to significant use of
PL/SQL.
For each sql statement in a PL/sql block, on each iteration, there
are
recursive calls to do the equivalent of bind and define."
This, and many other Oracle performance metrics are discussed in
my book "Oracle
Tuning" by Rampant TechPress. You can buy it directly from
the publisher and save 30% at this link:

Note:This Oracle
documentation was created as a support and Oracle training reference for use by our
DBA performance tuning consulting professionals.
Feel free to ask questions on our
Oracle forum.

Verify
experience!Anyone
considering using the services of an Oracle support expert should
independently investigate their credentials and experience, and not rely on
advertisements and self-proclaimed expertise. All legitimate Oracle experts
publish
their Oracle
qualifications.

Errata? Oracle technology is changing and we
strive to update our BC Oracle support information. If you find an error
or have a suggestion for improving our content, we would appreciate your
feedback. Just e-mail:
and include the URL for the page.